[单项选择]Vivid, violent dreams can portend brain disorders by half a century, a new study finds. Spotting early warning signs of the disease may (67) clinicians to monitor and treat patients long (68) the brain deterio-rates. People with a mysterious sleep disturbance (69) REM sleep behavior disorder, or RBD, experience a sudden change in the nature of dreams. Dreams increasingly become more violent and frequently (70) episodes in which an attacker must be fought (71) . The normal muscle paralysis that accompanies dreams is gone, (72) the dreamer, who is most often male, to act (73) the dream’s punches, twists and yells.
Doctors used to think of RBD as an isolated disorder. But follow-up studies (74) that a striking number of these patients later (75) neuro-degen-erative diseases, including Parkinson’s disease and Lewy body dementia. The exact figures (76) , but some studies find that anywhere from 80